The present invention relates to suction canisters of the type commonly used for collection of waste fluids from a medical patient, such as collection of the fluid drainage associated with a surgical site. These suction canisters include an open-top receptacle for the waste fluids and a lid which closes the open-top of the receptacle. The receptacle and the lid most commonly are fabricated from plastic materials by molding techniques. In plastic molding, the receptacle and the lid can not be formed as a complete unit due to physical limitations relating to the molding process. Therefore, the receptacle and lid are manufactured as separate units and must be assembled prior to use.
The fluids normally collected in a suction canister commonly contain infectious matter. Pursuant to acceptable operating procedures for medical facilities, the collected fluids are to be disposed of in a manner which destroys the infectivity potential of the fluids and/or canister, and which guards against inadvertent contact between the fluids and a health care worker. It is common therefore either to provide an inner liner within the canister which captures the fluids and which is removable for disposal, or to cap off the entry and exit openings to the canister and dispose of the fluids and canister simultaneously. The procedure employing a liner within the canister is intended to permit reuse of the canister and its lid, and therefore suffers from the problem of potential exposure to a health care worker when the lid is removed and the liner is closed and retrieved from the canister. In known prior art canister and lid combinations, the lid is secured to the open top end of the canister as by threads or by friction fit between the lid and the canister. These methods of attachment are intended to ensure a vacuum seal between the lid and the open end of the canister, hence each technique requires the health care worker to exert sufficient force to the lid to ensure that it seals properly with the canister. Further, each such technique provides a measure of adjustability with respect to the extent to which the lid can be applied to the canister, thereby requiring the health care worker to judge when the lid is sufficiently sealed to the canister. Through the natural tendency of a health care worker to want to ensure a good seal between the lid and the canister, the worker may tend to apply excessive force to the lid. This excessive force causes the lid to be inordinately difficult to remove when the canister is filled with liquids, so that removal of the lid under these circumstances subjects the worker to potential inadvertent exposure to the liquids if the force applied to remove the lid causes the lid to open in an uncontrolled manner. Both these prior lid attachment techniques permit removal of the lid after the canister contains fluids and therefore provide little or no assurance that the canister will not be opened, either purposefully or inadvertently, between its point of use and its point of final disposal.
It is therefore an object of the present invention to provide a suction canister which includes a receptacle and lid which can be readily assembled at the point of use, wherein the sealing of the lid to the open-top end of the receptacle is positive, and wherein the lid, after being assembled in sealing relationship to the receptacle, is essentially non removable by non-destructive force applied to the lid.
Other objects and advantages of the present invention will be recognized from the description contained herein including the claims and the drawings.